NEW YORK (AP) - NBC's "ER" ended its 15-year run Thursday much like it began, with a pulse-quickening symphony of life and death.

The medical drama earned a record 122 Emmy Award nominations since 1994, and its final episode mixed current cast members with old favorites from when it was television's most mighty hit.

"So? This is it?" an elderly man played by Ernest Borgnine said to John Stamos' Dr. Gates as the woman he'd loved since the sixth grade died in front of him.

The two-hour finale, written by old "ER" hand John Wells, had moments of dark humor - if projectile vomiting and an old man's penis fracture could be considered funny - and a career-questioning tragedy of a mother of five dying shortly after she gave birth to twin girls. The show left unanswered the question of whether a teenage girl put into a coma from a drinking binge would be brain-damaged.

It ended with a glimmer of hope. Dr. Mark Greene's daughter Rachel, 22, visits her late father's place of work and is bitten by the bug to follow him. Cameras pull away as the character, excitement on her face, follows stretchers filled with industrial accident victims into Chicago's County General Hospital.

Former cast members Eriq La Salle, Laura Innes, Sherry Stringfield and Alex Kingston returned for the finale. So did Noah Wyle, and his character of Dr. John Carter was central to Thursday's story, as he dedicated a new medical facility for the poor named for his late son and returned to County General for some nostalgic trips to the emergency room.

The series' biggest star, George Clooney, paid a final visit back to the show three weeks ago.

"ER" had begun its run with a two-hour pilot airing on Sept. 19, 1994, and became an instant hit. At its peak, it averaged 32 million viewers every episode, a level unimaginable in today's television world. NBC earned more than a half million dollars for 30 seconds of ad time on "ER" in the late 1990s; this season it charged less than $150,000, according to Horizon Media, Inc.

Before the finale began, Wells paid tribute to Michael Crichton, the late series creator. He said the last show "is a bit of an homage to what we did in the first episode, in the pilot. I felt as if he wrote it with me."

In its later years, "ER" was eclipsed by "House" and "Grey's Anatomy" among fans of medical dramas, and none of the leading cast members remained. The show's audience was less than a third of what "ER" drew in its mid-1990s peak.

The close of "ER" represents the end of an era for NBC. Through "Hill Street Blues,""L.A. Law" and finally "ER," NBC had a critically acclaimed drama on its schedule at 10 p.m. on Thursday nights since 1981. Thursday's powerful "must-see TV" schedule earned billions for NBC until it faded away with the death of shows like "Seinfeld" and "Friends."

Now a fourth-place network, NBC is giving up on programming dramas in that hour. Starting in the fall, Jay Leno will host a nightly comedy show that will air each weeknight at 10 p.m. 

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